Sen. Marco Rubio scored a key endorsement on Tuesday as South Carolina Sen. Tim Scott gave the Republican presidential hopeful his backing.

In a video posted to Rubio's Youtube page, Scott said the Republican party has "one shot" to beat Hillary Clinton in 2016 and "that shot is Marco Rubio."

"I'm putting my confidence and trust in Marco Rubio because I believe he takes us to that better future," Scott said. "Marco Rubio understands that, here in America, it's not about where you start, but where you're going.

Rumors that Scott would back Rubio have swirled for some time, with the senator having appeared on the campaign trail with Rubio several times. Rep. Trey Gowdy — another South Carolinian who himself endorsed Rubio — last week said Scott would campaign for Rubio in the state, further hinting at an impending announcement.

Now that it's official, the endorsement is expected to give Rubio a boost in the crucial state of South Carolina — where the candidate may be looking to bag his first primary win.

Scott is one of South Carolina's most popular politicians — enjoying support from conservatives and moderates alike — and his endorsement coupled with Gowdy’s gives Rubio the backing of two of the most well-respected lawmakers in the state.